The causes of pain in the back of the foot in the morning are as follows: 1, local soft tissue injury: after a lot of sports during the day, it may cause strain strain injury of the fascia of the back of the foot, so in a quiet state at night, there may be pain in the back of the foot, and it may be felt after a sleep. 2, cold in the back of the foot: at night the cold wind, such as air conditioning blowing to the back of the foot, or the back of the foot is not kept warm. The quilt is not covered, which will cause the vasoconstriction of the dorsal foot, and therefore will manifest as numbness and soreness of the soft tissues of the dorsal foot. 3, gouty arthritis: after drinking a lot of alcohol or eating seafood, the first metatarsophalangeal joint, that is, the inner side of the dorsal foot, may become red, swollen and painful, which can only be clarified by a blood uric acid test at the hospital.